<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <form action="" method="get">
        <input type="text" name="user" id="">
        <input type="text" name="pass" id="">
        <button>submit</button>
    </form>
    
    <?php
        $user=$_REQUEST["user"];
        $pass=$_REQUEST["pass"];

    if(!$user||!$pass){
        die("");
    }

        $con=mysql_connect("localhost","root","root");

        mysql_select_db("user");
        mysql_query("set names utf8");

        $sql="insert into `va`  values (null,'$user','$pass')";

        mysql_query($sql);
        mysql_close($con)
    ?>
</body>
</html>